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convert a list of objects from one type to another using lambda expression
I have a foreach loop reading a list of objects of one type and producing a list of objects of a different type. I was told that a lambda expression can achieve the same result.
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Modifying a subset of rows in a pandas dataframe
...on criteria, columns I want] = value
So Bren's answer is saying 'find me all the places where df.A == 0, select column B and set it to np.nan'
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Mathematical functions in Swift
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UIKit, Cocoa, Foundation, all valid choices.
– erdekhayser
Nov 27 '14 at 20:26
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How do I provide JVM arguments to VisualVM?
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Kevin WelkerKevin Welker
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Coding Conventions - Naming Enums
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Technically, enum instances are classes. That's why they can have methods.
– Ted Hopp
Nov 15 '11 at 22:44
89
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With MySQL, how can I generate a column containing the record index in a table?
...l l
JOIN (SELECT @curRow := 0) r;
The JOIN (SELECT @curRow := 0) part allows the variable initialization without requiring a separate SET command.
Test case:
CREATE TABLE league_girl (position int, username varchar(10), score int);
INSERT INTO league_girl VALUES (1, 'a', 10);
INSERT INTO leag...
How to set a JVM TimeZone Properly
I am trying to run a Java program, but it is taking a default GMT timezone instead of an OS defined timezone. My JDK version is 1.5 and the OS is Windows Server Enterprise (2007)
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How can I backup a remote SQL Server database to a local drive?
... script" to "Schema and data" value
In the next four windows, hit 'select all' and then next,
Choose to script to a new query window
Once it's done its thing, you'll have a backup script ready in front of you. Create a new local (or remote) database, and change the first 'USE' statement in the s...
How do I efficiently iterate over each entry in a Java Map?
...erret The only reason you might want to use an iterator is if you need to call its remove method. If that is the case, this other answer shows you how to do it. Otherwise, the enhanced loop as shown in the answer above is the way to go.
– assylias
Oct 8 '12 at ...
Get a random boolean in python?
... but I found that random.getrandbits(1) to be quite a lot faster. If you really want a boolean instead of a long then
bool(random.getrandbits(1))
is still about twice as fast as random.choice([True, False])
Both solutions need to import random
If utmost speed isn't to priority then random.choic...